Keep reading to see the Zen mentioned.
I think you are confused - I asked you to find some supporting evidence. So far all you have done is ask me to find supporting evidence for your claims. There is a problem that is common with Zen Xtra. I am not going to tell you what it is - you will have to figure it out for yourself.
HINT: it has nothing to do with the battery cover.
BTW: There were two references to the Zen in the link you provided and neither one has anything to do with a broken battery cover.